1. Field of the Invention
The present invention is directed to x-ray examination installation which permits an x-ray examination subject optionally to be examined in a transillumination mode, or to have an x-ray exposure of a selected region produced.
X-ray examination installations which offer the possibility of producing a direct exposure of a diagnostically relevant region of a patient, the region being perceptible is a transillumination mode of the patient, are known in the art. An example of such an x-ray examination installation is described in the advertising brochure for "ANGIOSKOP A33" manufactured by Siemens Elema AB, Sweden. This installation has a x-ray diagnostics device including an adjustable C-bend with an x-radiator mounted at one end, and an x-ray image intensifier, for transillumination of the examination subject mounted at the opposite end. An exposure device is positionable opposite the x-radiator to obtain a radiographic exposure of the examination subject.
A sheet film changer is used as the exposure device, and is attached to the x-ray diagnostics device so as to be joined with the x-ray image intensifier to form a unit therewith which is pivotable around an axis so that either the x-ray image intensifier or the exposure is positionable opposite the x-radiator. This known thus permits a change from a transillumination mode to an exposure mode to be undertaken in a simple manner, by merely pivoting the unit consisting of the x-ray image intensifier and the exposure device to bring one of those components into the radiation field. The exposure device also follows arbitrary movements of the x-ray diagnostics device, because it is connected to the x-ray image intensifier, which is turn connected to the x-ray diagnostics device. A disadvantage is present in this installation, however, because the C-bend of the x-ray diagnostics device is loaded not only by the weight of the x-ray image intensifier and the x-radiator, but also by the weight of the exposure device. The C-bend and the bearing thereof, must consequently be solidly built, resulting in additional costs. Moreover, the unit consisting of the x-ray image intensifier and exposure device restricts the accessibility of the attendant or physician to the examination subject in certain examinations as a consequence of its considerable space requirements.